From the 1890s until the early 1930s, why were there very few movies in color produced?

This was due to the fact that there wasn’t much inventory in having color contrast in lens for the filming industry. when they began to see that they could use a color sheet and see through a prisma they could see the colors reflect onto the screen as shown from the other end of the lens.

Ibelieve the answer is the second one. plz don't kill me if i got it wrong. > .<

The period that marks the paleolithic era is between the 250,000 to 10,000 years.